Over the last decade, six amateur ice hockey players have died from seemingly innocent blows to the neck.

This pattern of sports-related death has thus far gone unnoticed -- with heart-related deaths getting the bulk of attention, writes Barry J. Maron, MD, with the Minneapolis Heart Institute Foundation.

His report is published in this week's Journal of the American Medical Association.

In fact, his study of 370 ice hockey players who died suddenly of heart-related causes focused on six fatal hockey injuries that occurred during games. All involved blunt and nonpenetrating blows.

In five cases, the fatal blows were inflicted to the neck by the puck -- four of those happened during play, while a fifth incident happened while the player was sitting on the team bench. In one case, an athlete was struck by a fist in a fight.

Each athlete collapsed immediately and resuscitation efforts were not successful.

Autopsies showed that in each case, an artery had ruptured leading to massive brain hemorrhage, Maron reports.

"The scenario of virtually instantaneous death during ice hockey competition in which high-velocity blows to the neck caused rupture of a major artery has been unappreciated," he writes.

Awareness of these risks is crucial to protecting athletes and enhancing the safety of ice hockey, he adds.